Put a Volquartsen trigger into my Ruger MKIV last night. Volquartsen's instructions and a Youtube video both stress care with the detent on the safety. Well--after about the third time of redoing part of it because of previous mistakes, I dropped the safety and the detent and spring disappeared. Searching for "MKIV safety detent" yielded several possibilities for MKI,II,and III. I found no source for the MKIV part. Does anyone know if the MKIV uses the same part? Seems logical that it wouldn't have changed, but...?